How to integrate Truelist with Brevo

Truelist has a direct integration with Brevo that validates your contact list and writes the validation result back to each contact as a custom attribute. This guide walks you through setup and day-to-day management.

How the integration works

When you connect Brevo, Truelist fetches all contacts from the list you select and runs each email address through its full validation pipeline. Once validation is complete, Truelist updates each Brevo contact with a custom attribute called TRUELIST_EMAIL_STATE:

  • valid — The email address is valid and safe to send to.
  • risky — The email address may be valid but carries some risk (e.g. disposable or role address).
  • invalid — The email address is invalid and should not be sent to.
  • unknown — Truelist could not determine the validity of the email address.

You can use this attribute in Brevo to build segments, suppress invalid addresses from campaigns and automations, and keep your contact list clean over time.

After setup, Truelist can validate your list automatically on a weekly basis, or you can trigger a sync manually at any time.

Before you begin

You will need a Brevo API key.

Finding your API key

  1. Log in to your Brevo account.
  2. Click your profile name (top-right) → Profile & Plan → SMTP & API.
  3. Go to the API Keys tab.
  4. Click Generate a new API key, give it a name (e.g. “Truelist”), and click Generate.
  5. Copy the key — it starts with xkeysib-.

Step-by-Step Setup

  1. Go to Settings → Integrations in your Truelist account.

  2. Find the Brevo card under Available integrations and click Set up.

  3. Paste your API Key into the field and click Save.

    Truelist will verify the key and create the integration.

  4. You will be taken to the Brevo settings page. Use the List dropdown to select the Brevo contact list you want to validate.

  5. Click Save.

  6. Click Sync now to kick off your first validation run.

    Important: You must select a list and click Save before clicking Sync now. Syncing without a list selected will not start.

Making the TRUELIST_EMAIL_STATE attribute visible in Brevo

Brevo requires you to manually add the TRUELIST_EMAIL_STATE attribute to the contact view before it appears on individual contact pages.

  1. In Brevo, go to Contacts → Settings → Contact attributes & CRM.
  2. Click Add a new attribute.
  3. Set the Attribute name to TRUELIST_EMAIL_STATE and the Type to Text.
  4. Click Save.

Once added, the attribute will appear on each contact’s detail page after the next sync.

Managing the Integration

Selecting a list

Use the List dropdown to choose which Brevo contact list Truelist should validate. After changing the list, click Save to apply.

Sync settings

Use the Status dropdown to control how syncing works:

  • Enabled, sync automatically — Truelist will validate your contact list on a weekly basis without any manual action.
  • Enabled, but sync manually — Syncing is enabled but will only run when you click Sync now.
  • Disabled — Syncing is paused. No new validations will run until you re-enable it.

Syncing now

Click the Sync now button to immediately kick off a validation of your selected Brevo list. Truelist will only validate email addresses that have not been validated recently. Existing results are cached and re-used based on your revalidation settings.

Deleting the integration

Click the Delete Brevo integration button to remove the connection entirely. This stops all syncing. It will not delete any data in Brevo or Truelist — your existing TRUELIST_EMAIL_STATE attributes and validation history are preserved. You can reconnect the integration at any time.

Using validation results in Brevo

Once a sync completes, each contact will have their TRUELIST_EMAIL_STATE attribute updated. Here are some common ways to put the results to use.

Suppress invalid addresses from campaigns

When creating a campaign, add a filter to exclude contacts where TRUELIST_EMAIL_STATE equals invalid. This prevents sending to bad addresses that would raise your bounce rate.

Build a clean segment for high-value sends

Create a segment in Brevo with the condition TRUELIST_EMAIL_STATE = valid. Use this segment for re-engagement campaigns or any send where deliverability is critical.

Quarantine risky addresses

Create a separate segment for contacts where TRUELIST_EMAIL_STATE = risky. You can choose to suppress these from regular sends while continuing to email validated addresses, or review them manually before deciding.

Remove unknowns after repeated syncs

If a contact still has TRUELIST_EMAIL_STATE = unknown after two or three sync cycles, consider suppressing or removing them. A persistent unknown result often indicates a problematic address.

Frequently Asked Questions

How often will my Brevo list sync automatically?

When set to automatic, Truelist will sync your list once per week.

Will Truelist re-validate contacts it has already checked?

Yes. Truelist re-validates existing contacts according to the revalidation period configured in your validation settings. The default is 60 days.

Can I validate my list on demand?

Yes. Click Sync now on the Brevo integration settings page to trigger an immediate validation run. Make sure you have selected a list and clicked Save first.

Does Truelist validate all contacts or just new ones?

Each sync fetches all contacts from your selected Brevo list. Truelist skips addresses that were validated recently (within your revalidation window) and only runs validation on new or stale addresses, so credits are not wasted on re-checking recent results.

Will the integration change any contact data other than TRUELIST_EMAIL_STATE?

Truelist only writes the TRUELIST_EMAIL_STATE custom attribute. It does not modify any other contact fields, delete contacts, or unsubscribe anyone.

What happens if my Brevo API key changes?

If Truelist cannot authenticate with Brevo during a sync, the integration will be automatically disabled and you will receive an email notification. Go to Settings → Integrations → Brevo and re-enter your API key to reconnect.

Why can’t I see TRUELIST_EMAIL_STATE on a contact’s page?

You need to add the attribute to Brevo’s contact view first. Go to Contacts → Settings → Contact attributes & CRM, add TRUELIST_EMAIL_STATE as a Text attribute, and it will appear on all contact pages going forward. See Making the attribute visible above.